The engineer on Amtrak #188, Brandon Bostian, 32 yoa, seems to have been mature, well-balanced, well-liked, and enthusiastic about his work as an Amtrak engineer.
Whether he was at the beginning of his shift, near the end of his shift, or how long his shift was, is not yet known.
Whether anyone was in the engine with him is not yet known. There appears to have been a central aisle from one end of the engine to the other. Whether the controls in the rear of the engine could be locked-out or had been locked-out in the front by Bostian is not known. Whether the doors to the engine could be locked and whether Bostian had locked them is not known. Whether the business class car just behind the engine had access to the engine door is not known -- although one surmises that preserving such access may have been customary.
The engine was an essentially-brand-new Cities Sprinter ACS-64 electric engine built by Siemens Corporation. Behind that were 7 cars.
There are a few ways to slow the train down -- by electrical resisitance within the engine wheels, by engine brakes, and by brakes within each vehicle in the 1-engine-followed-by-7-car passenger train. The latter means of braking was probably the safest. It would distribute the braking momentum transfer into the rails and railroad ties beneath over the length of the train.
The tracks appear to have been somewhat unitized, if you look at aerial photos of the tracks before the accident, aerial photos of the tracks just after the accident, and photos of new track being carted-in by truck to replace the destroyed truck. A simple question; When track units are installed, how are they anchored to the railroad right-of-way -- or do they just "float," on trap rock or dirt? In other words, could a heavy, suddenly-braking engine or train literally yank a section of track off its bed? Is there an amazing secret defect in the track design, generated, for instance, by some moron's desire to economize a little too much in the face of Amtrak's ever-shrinking federal subsidies and the really bad economy since 2007? Is there an Amtrak executive who is hiding the fact of an unwise purchase of a new type of track?
At Frankford Junction, the tracks were banked for speed, being higher on the outside side of the curb by 5" per width of track. That's a pretty good embankment. Any calculation of listing by the train toward the outside of the curve due to centrifugal force in turning has to overcome a pre-existing listing and centripital pulling toward the inside of the curve, first, due to that track-embankment-generated listing.
News reports showing a railroad "expert" claiming that the train could jump track if the train's speed exceeded the speed limit by as little as 5 mph have to be wildly "over-conservative" and so dead false.
When I was a young man, the Metroliners used to "blow through" that banked turn at a frightening speed -- well over 50 mph. I remember see that little trash-bearing wake of air trapped by the slipstream behind the passing Metroliners headed into that banked curve.
So, the 50 mph speed limit for what appears to be brand new well-banked track (see next paragraph) is interesting.
... make it look like a sharp turn.
In fact, it is a very gentle turn. See Google Maps, Earth Image, at ...
https://www.google.com/maps/@40.0013838,-75.0944874,161m/data=!3m1!1e3?hl=en
At the moment of departure, #188 had 238 passengers and 5 crew. The ages of those passengers seem importance. For example, were there any kids in the first passenger car -- the Business Class car -- just behind the engine? Did a kid cross from the Business Class car to the engine -- even with a parent's permission -- to allow him or her to experience the thrill of being in the engine?
#188 left 30th Street Station at exactly 9:09 p.m., according to Amtrak's schedule. Bostian moved the train north out of the station up the tracks on the west bank of the Schuyhkill River, past the west side of the Philadelphia Zoo, and then eastward across the Schuylkill River over the old stone arch Connecting Railway Bridge, to the Northeast Corridor tracks running diagonally, northeast across North Philadelphia, to North Philadelphia Station at Broad Street and West Glenwood Avenue, between Lehigh and Allegheny Avenues.
The train apparently did not stop at North Philadelphia Station. Did someone at North Philadelphia Station make improper entry into the engine from the platform between the engine and the Business Class car as the train slowed? Is this possible?
The train continued northeast across North Philadelphia, and swung rightwards, behind St. Christopher's Hospital at Front Street between Eire and Tioga, so that it traveling east, toward Frankford Junction and the Frankford Junction curve.
As stated above, the "terrible" curve at Frankford Junction is a leftward turn toward the Northeast at the rate of about 3.3 degrees per 100 feet (so that in the 1200 feet between the point of intersection with Frankford Avenue and the point of intersection with the line through Wheatsheaf Lane, the track has turned about 40 degrees north northeast). If you plug that into the formula for achieving balancing speed -- the speed along a track banked for speed where the train is in equipoise, falling neither toward the inside of the curve nor toward the outside of the curve ...
... where "Vmax" is mph, "Ea" is the number of inches the outside rail is higher than the inside rail, and "d" is the number of degrees turned per 100 feet, you get 58 mph.
Now, clearly, if the train can lean in toward the inside of the curve without derailing and falling inward, at 1 mph, where the tracks are so seriously banked that it has to go 58 mph before it reaches equipoise, it would seem to be able to rather easily take the curb at even 116 mph -- twice 58 mph -- without derailing outwards, toward the outside of the curve.
Bostian seems to have had #188 cruising along at roughly 70 mph as he began to close in on the Frankford Junction curve, where the posted speed limit is an inexplicable 50 mph (where, again, 58 mph is equipoise, given the grade).
Instead of slowing down to the posted speed limit, after that, #188 inexplicably increased its speed, so that it reached a maximum of 107 mph before it reached the curb.
Why?
Was Bostian fatigued, so that he forgot that he had not even passed Frankford Junction yet, and thought that he was on the straightaway northeast of Frankford Junction along the Delaware?
Did he actually begin braking the train, so that momentum spilled his water bottle into the apparatus, short-circuiting the accelerator slide and generating a sudden increase toward maximum speed?
Did a water bottle left by someone on the controls at the other end of the engine do this?
Unknown to all, did a vandal tossing a rock "get lucky" and pierce the windows next to the controls and slam the accelerator slide to the "maximum speed" position? In other words, was Bostian shocked and puzzled by the velocity increase?
Did a child or malicious teenager from the North Philadelphia platform or from the Business Class car tamper with controls?
Who knows?
That is the question of all questions.
In judging this question, remember four (4) words -- the "Toyota Unintended Acceleration Problem."
In other words, was Bostian;'s Cities Sprinter ACS-64 electric engine merely the first one to do this, with fatal results.
This is not an idle question.
Here's another angle worthy of investigation: One problem with today's nuclear power plants is the layering of safety systems upon the basic mechanism, and the layering of second layer safety systems upon the first -- generating a mechanism so frighteningly complex that no human being is safe around them. With that in mind ...
Is it possible that the federal government's own Positive Train Control System mandate interface mechanism somehow caused the problem?
In any event, just as #188 was entering the Frankford Junction curve, Bostian threw on the brakes.
Now, again, I believe that, contrary to all media reports and executive speculation within Amtrak and the National Transportation Safety Board, in my opinion #188 could have easily taken the curb.
However, when Bostian threw on the brakes -- something every human being in his position, including every Amtrak executive, every National Transportation Safety Board investigator, Mayor Wilson Good and the District Attorney, and everyone else who has opened his mouth in angry criticism, would have done in this case -- the passengers felt a terrible vibration.
That would have been the brake-frozen wheels vibrating their way down the curb.
I believe that the vibration is what derailed the train. Suddenly, the net effect of all of those wheels bbbbbbbbbbrrrrrrrrrrpppppppppping their way down the track, so that, on the average, the train was somewhat "airborne" during every second of breaking, markedly decreasing each railroad vehicle's right wheels' flanges on the inside surface of the outside rail, at 104 mph -- the train's last known speed before departing from the railways over the outward side of the curve -- contributed heavily to the derailment.
I would also be interested in the relative integrity of the brake pads in the cars behind the engine.
The engine was effectively brand new -- with new brakes.
If the railroad cars behind it only had older brakes that only held "half as good," their would have been a "ramming" effect by the momentum in the rear cars. Just as you can't push a length of rope into a mouse hole, the cars in the rear aren't going to happily slow down for the engine if the engine stops better than they do.
They are going to want to pile-up against the engine's rear.
I believe that that contributed very heavily to the derailment -- and that that is why the first passenger car behind the engine was bent into the shape of a giant horse shoe.
Perhaps it was the passenger cars slamming the engine from behind because of their inferior brakes that pushed the violently vibrating engine off the tracks.
So, Bostian threw on the brakes.
#188 began bbbbbbbbbbrrrrrrrrrrpppppppppping its way down the track, into the curb.
The cars begin the Business Class car, the first passenger car, rammed it hard and bent it into a horseshoe shape.
As this was occurring, the engine derailed, and simply proceeded in a straight line from the point of derailment.
The cars behind the Business Class car cast the Business Class car to the left, making those cars bounce right well off the track as the train continue forward from momentum.
And then it all ground to a halt.
We should not pre-judge Bostian.
No comments:
Post a Comment